The main purpose of the Buick tie rod is to connect the wheel to the steering components of your car. They are generally a straight bar with a ball joint connected to it that is at a 90 degree angle from the bar with a metal stud protruding from it. This stud is the portion of the tie rod that is connected to the spindle of the car which turns the wheel. The other end is screwed into the connecting bar which receives input to the direction the car is to travel from the steering column. If there is a zerk on the ball joint of your Buick tie rod, it should be greased when you have the oil changed in your car or every 3,000 miles. This is included in the periodic maintenance that all Buick cars should receive. The grease helps to prevent the premature aging and wearing of the part so the owner can experience better handling for a longer period of time. If the tie rod on your Buick is worn, it can be noticed with the play of the steering wheel increasing over time. There are 2 tie rod assemblies consisting of a pair of inner and a pair of outer tie rod ends on your car. If one has been recommended to be replaced, the other should also be changed out at the same time. Once this is accomplished the input from the steering wheel will appear to be tighter to the driver of the Buick. The tie rod on your car has a secondary purpose. This is the part of the steering system that the toe of the front wheels is adjusted. This is the inward and outward position the front wheels are placed in to help keep your car going straight down the road with minimal wear on the tires.